Developmental perturbation induced by maternal asthma during pregnancy: the short- and long-term impacts on offspring

Maternal asthma in relation to infant size and body composition

Background

Asthma affects 10% of pregnancies and may influence offspring health, including infant size and body composition, through hypoxic and inflammatory pathways.

Objective

We sought to determine associations between maternal asthma and asthma phenotypes during pregnancy and infant size and body composition.

Methods

The B-WELL-Mom study (2015-19) is a prospective cohort of 418 pregnant persons with and without asthma recruited in the first trimester of pregnancy from 2 US obstetric clinics. Exposures were maternal self-reported active asthma (n = 311) or no asthma (n = 107), and asthma phenotypes were classified on the bases of atopy, onset, exercise induced, control, severity, symptomology, and exacerbations. Outcomes were infant weight, length, head circumference, and skinfold measurements at birth and postnatal follow-up, as well as fat and lean mass assessed by air displacement plethysmography at birth. Adjusted multivariable linear regression examined associations of maternal asthma and asthma phenotypes with infant outcomes.

Results

Offspring were born at a mean ± SD of 38 ± 2.3 weeks' gestation and were 18 ± 2.2 weeks of age at postnatal follow-up. Infants of participants with asthma had a mean ± SD fat mass of 11.0 ± 4.2%, birth weight of 3045.8 ± 604.3 g, and postnatal follow-up weight of 6696.4 ± 964.2 g, which were not different from infants of participants without asthma (respectively, β [95% confidence interval]: -0.1 [-1.4, 1.3], -26.7 [-156.9, 103.4], and 107.5 [-117.3, 332.3]). Few associations were observed between asthma or asthma phenotypes and infant size or body composition.

Conclusions

In a current obstetric cohort, maternal asthma during pregnancy was not associated with differential infant size or body composition.

Mitochondria signaling pathways in allergic asthma

Mitochondria, as the powerhouse organelle of cells, are greatly involved in regulating cell signaling pathways, including those related to the innate and acquired immune systems, cellular differentiation, growth, death, apoptosis, and autophagy as well as hypoxic stress responses in various diseases. Asthma is a chronic complicated airway disease characterized by airway hyperresponsiveness, eosinophilic inflammation, mucus hypersecretion, and remodeling of airway. The asthma mortality and morbidity rates have increased worldwide, so understanding the molecular mechanisms underlying asthma progression is necessary for new anti-asthma drug development. The lung is an oxygen-rich organ, and mitochondria, by sensing and processing O2, contribute to the generation of ROS and activation of pro-inflammatory signaling pathways. Asthma pathophysiology has been tightly associated with mitochondrial dysfunction leading to reduced ATP synthase activity, increased oxidative stress, apoptosis induction, and abnormal calcium homeostasis. Defects of the mitochondrial play an essential role in the pro-remodeling mechanisms of lung fibrosis and airway cells' apoptosis. Identification of mitochondrial therapeutic targets can help repair mitochondrial biogenesis and dysfunction and reverse related pathological changes and lung structural remodeling in asthma. Therefore, we here overviewed the relationship between mitochondrial signaling pathways and asthma pathogenic mechanisms.

The impact of maternal asthma during pregnancy on fetal growth and development: a review

INTRODUCTION

Asthma is a highly prevalent co-morbidity during pregnancy that can worsen as gestation progresses and is associated with several adverse perinatal outcomes. These adverse outcomes often result from uncontrolled asthma during pregnancy and acute asthma exacerbations that are associated with alterations in placental function and fetal growth.

AREAS COVERED

This paper will discuss how maternal asthma in pregnancy affects fetal growth and development which may alter future offspring health. Changes in placental function occur in a sex-specific manner in pregnancies complicated by asthma and result in differences in fetal growth and development which may influence child health. The follow up of children from mothers with asthma suggests they are at greater risk of developing asthma, have alterations in microvascular structure that may contribute to a future risk of cardiovascular disease and epigenetic modifications in immune cell function. The current evidence suggests that appropriately managed asthma during pregnancy results in normal fetal growth and development.

EXPERT OPINION

Clinical management of asthma during pregnancy needs significant improvement to prevent adverse outcomes for the fetus. The key to improving maternal and fetal outcomes is through education of health professionals and parents about controlling asthma during pregnancy.

Impact of parental asthma, prenatal maternal asthma control, and vitamin D status on risk of asthma and recurrent wheeze in 3-year-old children

BACKGROUND

While familial clustering of asthma is known, few studies have reported on the relative roles of paternal and maternal asthma and the role of maternal asthma control in pregnancy on the risk for asthma in the child.

OBJECTIVE

We aimed to investigate the relative roles of paternal asthma, maternal asthma, and maternal asthma control during pregnancy on the risk of asthma or recurrent wheeze in 3-year-old children and how prenatal and cord blood vitamin D status might affect this risk.

METHODS

Data from 806 women, their partners (biologic fathers of the infants), and their children participated in the Vitamin D Antenatal Asthma Reduction Trail (VDAART, clinicaltrials.gov identification number NCT00920621) were used for this cohort analysis. The parental report of physician-diagnosed asthma or recurrent wheeze in offspring was the main outcome. Weibull regression models for interval-censored event times were used to estimate the main variables of interests and additional covariates on the outcome.

RESULTS

The highest risk was observed among children with both parents being asthmatic relative to non-asthmatic parents (aHR = 2.30, 95% CI: 1.35-3.84), and less so if only the mother was asthmatic (aHR = 1.70, 95% CI: 1.17-2.40). In the subset of children born to asthmatic mothers, the risk for asthma was higher in those who were born to mothers whose asthma was uncontrolled (aHR = 1.60, 95% CI: 1.02-2.54). Children whose mothers had sufficient vitamin D status (25Hydroxyvitamin D ≥ 30 ng/mL) at early and late pregnancy and had cord blood vitamin D sufficiency demonstrated a lower risk of asthma/recurrent wheeze than children who had insufficient cord blood vitamin D status at birth (aHR = 0.47, 95% CI: 0.27-0.83).

CONCLUSION AND CLINICAL RELEVANCE

Careful attention to maternal asthma control, monitoring vitamin D status, and correcting insufficiency at early pregnancy and maintaining the sufficiency status throughout pregnancy have potential preventive roles in offspring asthma or recurrent wheeze.

Impact of Preeclampsia on the Relationship between Maternal Asthma and Offspring Asthma. An Observation from the VDAART Clinical Trial

RATIONALE

Maternal asthma and preeclampsia have independently been reported to be associated with increased asthma incidence in children of affected mothers. Maternal asthma is also associated with increased risk of preeclampsia development. However, the joint effect of these maternal conditions on child asthma risk is unknown.

OBJECTIVES

To study whether development of preeclampsia among pregnant women with asthma was associated with higher risk of childhood asthma in the VDAART (Vitamin D Antenatal Asthma Reduction Trial).

METHODS

A total of 806 pregnant women and their offspring at high risk of asthma or atopy, who were followed from VDAART enrollment (10-18 wk of gestation) through the child's third birthday, were included in this cohort analysis. Preeclampsia status was determined by chart review, obstetrician diagnosis, and adjudication by a panel of obstetricians. Child asthma was the main outcome as determined by parental report of a physician diagnosis, and the risk of child asthma was also examined if accompanied by recurrent wheeze. The main risk variable of interest was a four-level ordered variable defined for each mother, with values without asthma without preeclampsia, without asthma with preeclampsia, with asthma without preeclampsia, and with asthma with preeclampsia during their pregnancy. We examined the trend of outcome proportions across these categories. To account for differences in maternal and child characteristics, we used a Weibull regression model for interval-censored data to compare the incidence of child asthma by age of 3 years across the maternal variable categories.

MEASUREMENTS AND MAIN RESULTS

The incidence of asthma in 3-year-old children was 9.90% (44/445), 17.95% (7/39), 22.11% (65/294), and 32.14% (9/28) among those born to mothers without asthma and without preeclampsia, mothers without asthma with preeclampsia, mothers with asthma without preeclampsia, and mothers with asthma with preeclampsia, respectively. The incidences demonstrated an increasing trend in risk of child asthma across the maternal groups (P for trend <0.001). After accounting for potential confounders and using time to report of childhood asthma as analysis outcome, risk of asthma was greater among children born to mothers with asthma without preeclampsia, compared with mothers without asthma without preeclampsia (adjusted hazard ratio, 2.18; 95% confidence interval, 1.46-3.26). This risk was 50% greater for children born to mothers with asthma who developed preeclampsia during pregnancy (adjusted hazard ratio, 2.68; 95% confidence interval, 1.30-5.61). The trend in asthma and recurrent wheeze proportions across the maternal groups' children also indicated a higher risk for children born to mothers with asthma with preeclampsia (adjusted hazard ratio, 4.73; 95% confidence interval, 2.20-10.07; P for trend <0.001).

CONCLUSIONS

Preeclampsia is associated with increased risk of early life childhood asthma in children less than 3 years old over and above that associated with maternal asthma alone. The results implicate the interplay between maternal factors as strong predictors of offspring asthma and in utero maternal-fetal immune perturbations and developmental dysregulations associated with preeclampsia.

Sex-specific impact of asthma during pregnancy on infant gut microbiota

Asthma during pregnancy is associated with retardation of fetal growth in a sex-specific manner. Lactobacilli microbes influence infant growth. This study aimed to determine whether lactobacilli and other microbes are reduced in the gut of infants born to an asthmatic mother, and whether this differs by the sex of the infant.

Mother-infant pairs (N=1021) from the Canadian Healthy Infant Longitudinal Development full-term cohort were studied. The abundance of infant faecal microbiota at 3–4 months, profiled by gene sequencing, was compared between both women with and without asthma treatment during pregnancy. Infant sex, maternal ethnicity, pre-pregnancy overweight and atopy status, birth mode, breastfeeding status and intrapartum antibiotic treatment were tested as covariates.

Independent of birth mode and other covariates, male, Caucasian infants born to women with prenatal asthma harboured fewer lactobacilli in the gut at 3–4 months of age. If asthmatic mothers had pre-pregnancy overweight, the abundance of Lactobacillus in males was further reduced in the infant gut, whereas the microbiota of female infants was enriched with Bacteroidaceae. Similar differences in infant gut microbial composition according to maternal prenatal asthma status were also more evident among women with food or environmental allergies.

Gut lactobacilli were less abundant in male infants, but Bacteroidaceae were more abundant in female infants at 3–4 months of age, following maternal asthma during pregnancy.

Gut lactobacilli are less abundant at 3–4 months in male but not female infants following maternal prenatal asthmahttp://ow.ly/jXnl30fU9xH

Review: Placental adaptations to the presence of maternal asthma during pregnancy

Asthma is a highly prevalent chronic medical condition affecting an estimated 12% of pregnant, women each year, with prevalence of asthma greatest (up to 16%) among the socially disadvantaged. Maternal asthma is associated with significant perinatal morbidity and mortality including preterm births, neonatal hospitalisations and low birthweight outcomes each year. We have identified that the placenta adapts to the presence of chronic, maternal asthma during pregnancy in a sex specific manner that may confer sex differences in fetal outcome. The male fetus was at greater risk of a poor outcome than a female fetus in the presence of maternal asthma and an acute inflammatory event such as an asthma exacerbation. This review will examine the role of sex specific differences in placental function on fetal growth and survival.

Patterns, predictors and outcomes of asthma control and exacerbations during pregnancy: a prospective cohort study

There exists a paucity of data for socially disadvantaged populations describing patterns and predictors of asthma control status and exacerbations during pregnancy, and their relationship to adverse perinatal outcomes.

Asthmatic women (n=189) were followed prospectively during pregnancy, with visits at 12, 20, 28 and 36 weeks gestation. Data on loss of control, recurrent uncontrolled asthma and moderate/severe exacerbations were collected at each visit and their relationship to perinatal outcomes examined following stratification for fetal sex.

50% of asthmatic women experienced a loss of control or moderate/severe exacerbation during pregnancy, with 22% of women experiencing a moderate/severe exacerbation. Factors associated with an increased risk of women experiencing recurrent uncontrolled asthma during pregnancy included smoking (relative risk 2.92, 95% CI 1.53–5.58), inhaled corticosteroid use at the beginning of pregnancy (relative risk 2.40, 95% CI 1.25–4.60) and increasing maternal age (relative risk 1.06, 95% CI 1.01–1.11). No factors were associated with moderate/severe exacerbations. Asthma control rather than exacerbations during pregnancy appeared to be most strongly correlated with perinatal outcomes. Following stratification by fetal sex, the presence of recurrent uncontrolled asthma was associated with an increased risk of being small for gestational age in women pregnant with females (33.3% versus 9.5%; p=0.018). In contrast, there was a nonsignificant increased risk of preterm birth in women with recurrent uncontrolled asthma that were pregnant with males (25.0% versus 11.8%; p=0.201)

These results suggest that the key to improving perinatal outcomes lies in improving asthma control as early as possible in pregnancy and monitoring throughout pregnancy, rather than focusing on preventing exacerbations alone.

Recurrent uncontrolled asthma during gestation is a greater contributor to poor perinatal outcomes than exacerbationshttp://ow.ly/X0OSa

Rejuvenating cellular respiration for optimizing respiratory function: targeting mitochondria

Altered bioenergetics with increased mitochondrial reactive oxygen species production and degradation of epithelial function are key aspects of pathogenesis in asthma and chronic obstructive pulmonary disease (COPD). This motif is not unique to obstructive airway disease, reported in related airway diseases such as bronchopulmonary dysplasia and parenchymal diseases such as pulmonary fibrosis. Similarly, mitochondrial dysfunction in vascular endothelium or skeletal muscles contributes to the development of pulmonary hypertension and systemic manifestations of lung disease. In experimental models of COPD or asthma, the use of mitochondria-targeted antioxidants, such as MitoQ, has substantially improved mitochondrial health and restored respiratory function. Modulation of noncoding RNA or protein regulators of mitochondrial biogenesis, dynamics, or degradation has been found to be effective in models of fibrosis, emphysema, asthma, and pulmonary hypertension. Transfer of healthy mitochondria to epithelial cells has been associated with remarkable therapeutic efficacy in models of acute lung injury and asthma. Together, these form a 3R model--repair, reprogramming, and replacement--for mitochondria-targeted therapies in lung disease. This review highlights the key role of mitochondrial function in lung health and disease, with a focus on asthma and COPD, and provides an overview of mitochondria-targeted strategies for rejuvenating cellular respiration and optimizing respiratory function in lung diseases.

Infant antibiotic exposure and the development of childhood overweight and central adiposity

BACKGROUND

Obesity has been associated with disruption of the gut microbiota, which is established during infancy and vulnerable to disruption by antibiotics.

OBJECTIVES

To investigate the association between early-life antibiotic exposure and subsequent development of overweight and central adiposity.

METHODS

Provincial health-care records were linked to clinical and survey data from a Canadian longitudinal birth cohort study. Antibiotic exposure during the first year of life was documented from prescription records. Overweight and central adiposity were determined from anthropometric measurements at ages 9 (n=616) and 12 (n=431). Associations were determined by multiple logistic regression.

RESULTS

Infants receiving antibiotics in the first year of life were more likely to be overweight later in childhood compared with those who were unexposed (32.4 versus 18.2% at age 12, P=0.002). Following adjustment for birth weight, breastfeeding, maternal overweight and other potential confounders, this association persisted in boys (aOR 5.35, 95% confidence interval (CI) 1.94-14.72) but not in girls (aOR 1.13, CI 0.46-2.81). Similar gender-specific associations were found for overweight at age 9 (aOR 2.19, CI 1.06-4.54 for boys; aOR 1.20, CI 0.53-2.70 for girls) and for high central adiposity at age 12 (aOR 2.85, CI 1.24-6.51 for boys; aOR 1.59, CI 0.68-3.68 for girls).

CONCLUSIONS

Among boys, antibiotic exposure during the first year of life was associated with an increased risk of overweight and central adiposity in preadolescence, indicating that antibiotic stewardship is particularly important during infancy. Given the current epidemic of childhood obesity and the high prevalence of infant antibiotic exposure, further studies are necessary to determine the mechanisms underlying this association, to identify the long-term health consequences, and to develop strategies for mitigating these effects when antibiotic exposure cannot be avoided.

Long-term effects of prenatal stress and glucocorticoid exposure

There is a growing body of evidence suggesting that events during prenatal life can have long-lasting effects on development and adult health. Stress during pregnancy is common and has been linked to increased incidence of a range of affective and behavioral outcomes in the offspring in later life and also some somatic outcomes. Glucocorticoids, and their actions on the fetus, which are regulated by placental 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2), are hypothesized to mediate these effects. Animal studies have demonstrated long-term effects of stress and glucocorticoid administration on behavioral outcomes, as well as increased blood pressure, altered hypothalamic pituitary adrenal axis (HPA) function, and decreased glucose tolerance and brain size. In humans, licorice, which inhibits placental 11β-HSD2 when consumed during pregnancy, has been shown to increase the risk of behavioral problems linked to altered HPA activity. Synthetic glucocorticoids administered during pregnancy to improve fetal lung maturity in threatened preterm birth have been shown to reduce birth weight and head circumference, but have not been linked to gross changes in long-term health to date. It is important to consider the long-term consequences of stress, and medication that mimics stress, during pregnancy.

Neonatal health of infants born to mothers with asthma

BACKGROUND

Maternal asthma is associated with serious pregnancy complications, but newborn morbidity is understudied.

OBJECTIVE

We wanted to determine whether infants of asthmatic mothers have more neonatal complications.

METHODS

The Consortium on Safe Labor (2002-2008), a retrospective cohort, included 223,512 singleton deliveries at ≥ 23 weeks' gestation. Newborns of mothers with asthma (n = 17,044) were compared with newborns of women without asthma by using logistic regression models with generalized estimating equations to calculate adjusted odds ratios (ORs) and 95% CIs. Electronic medical record data included gestational week at delivery, birth weight, resuscitation, neonatal intensive care unit (NICU) admission, NICU length of stay, hyperbilirubinemia, respiratory distress syndrome, apnea, sepsis, anemia, transient tachypnea of the newborn, infective pneumonia, asphyxia, intracerebral hemorrhage, seizure, cardiomyopathy, periventricular or intraventricular hemorrhage, necrotizing enterocolitis, aspiration, retinopathy of prematurity, and perinatal mortality.

RESULTS

Preterm delivery was associated with maternal asthma for each week after 33 completed weeks of gestation and not earlier. Maternal asthma also increased the adjusted odds of small for gestational age (OR = 1.10; 95% CI, 1.05-1.16), NICU admission (OR = 1.12; 95% CI, 1.07-1.17), hyperbilirubinemia (OR = 1.09; 95% CI, 1.04-1.14), respiratory distress syndrome (OR = 1.09; 95% CI, 1.01-1.19), transient tachypnea of the newborn (OR = 1.10; 95% CI, 1.02-1.19), and asphyxia (OR = 1.34; 95% CI, 1.03-1.75). Findings persisted for term infants (≥ 37 weeks) who had additional increased odds of intracerebral hemorrhage (OR = 1.84; 95% CI, 1.11-3.03) and anemia (OR = 1.30; 95% CI, 1.04-1.62).

CONCLUSIONS

Maternal asthma was associated with prematurity and small for gestational age. Adverse neonatal outcomes, including respiratory complications, hyperbilirubinemia, and NICU admission, were increased in association with maternal asthma even among term deliveries.